1. Field
The present disclosure relates to a turbofan used in an air conditioning apparatus. More particularly, the present disclosure relates to a similar three-dimensional turbofan that can be manufactured by upper and lower dies without use of complex multiple slide dies and has performance improved than a two-dimensional turbofan, and an air conditioning apparatus using the same.
2. Description of the Related Art
A turbofan which is widely used in air conditioning apparatuses is configured of a shroud, a hub plate, and a plurality of blades arranged circumferentially between the shroud and the hub plate.
Such a turbofan may be classified into a two-dimensional turbofan and a three-dimensional turbofan in accordance with a shape of the blade.
Because a two-dimensional turbofan 100, as illustrated in FIGS. 1A and 1B, has a structure in which a plurality of blades 130 is disposed perpendicular to a hub plate 110 and a shroud 120, the two-dimensional turbofan 100 may be molded as a single body that the shroud 120, the hub plate 110, and the plurality of blades 130 are formed integrally by using a mold that can be separated up and down.
Because the structure of the mold is simple, the production cost of the two-dimensional turbofan 100 is low. However, because the shape of the blade 130 cannot be freely designed, there is a limitation to improve power consumption and noise of the two-dimensional turbofan 100.
On the other hand, as illustrated in FIG. 2, a three-dimensional turbofan 200 is formed so that a hub plate 210, a shroud 220, and a plurality of blades 230 are molded by a separate mold, respectively, and then these parts are welded by ultrasonic welding or laser welding.
Because the shape of the blade 230 can be freely designed and manufactured, the three-dimensional turbofan 200 has advantage in the power consumption and noise compared to the two-dimensional turbofan 100. However, in the production side, the three-dimensional turbofan 200 has a disadvantage that the production cost is high since three kinds of molds are used for molding the hub plate 210, the shroud 220, and the blades 230 and the plurality of blades 230, for example, seven blades 230 in FIG. 2 are welded to both the shroud 220 and the hub plate 210. Also, because of burrs, etc. generated when the plurality of blades are welded to the shroud and the hub plate, the appearance quality of the three-dimensional turbofan is not good.
Accordingly, the development of a new turbofan that can reduce the power consumption and noise in comparison to the two-dimensional turbofan and that can reduce the production cost and enhance the appearance quality compared to the three-dimensional turbofan has been required.